Material surface testing apparatus



April 1963 T. F. M DONNELL 3,087,326

MATERIAL SURFACE TESTING APPARATUS Filed April 1. 1960 r/HE) INVENTORE47A fit, 7 m

ATTORNEY mam 5 F. MM Dav/V524.

3,317,325 Patented Apr. 39, 1963 3,087,326 MATERHAL SURFAfJE TESTINGAPPARATUS Thomas F. MacDonneil, Newark, NJ assignor to Nopco ChemicalCompany, Newark, NJL, a corporation of New Jersey Filed Apr. 1, 1960,Ser. No. 19,227 Claims. ((31. 73--7) This invention relates to novelapparatus for determining scuff resistance and/or surface break-down ofvarious materials. In one of its more specific aspects the invention isdirected to novel apparatus for determining the scuff-resistance and/orsurface break-down of paper especially as well as other flexible sheetmaterials, such as paperboard, natural and artificial leathers, textilesmade of natural and/or synthetic fibers such as cotton, silk, Wool,Orlon, nylon, Dacron, etc. In one of its more specific aspects theinvention is especially directed to apparatus for determining andascertaining the scuff-resistance and/ or surface break-down of theouter surfaces of said materials, which surface may be a coated-finishedsurface, treated or sized surface.

For many years such materials having been treated with a great varietyof substances to coat and in some cases also to impregnate sametherewith for the purpose of imparting at least a certain characteristicthereto. And, such characteristic imparted thereto is dependent upon theparticular treating material employed.

The main purpose of this invention is to provide novel apparatus foreasily and readily determining and ascertaining the scuff resistanceand/or surface break-down of such surface treated materials. Byemploying the present invention, it is possible to obtain ascuff-resistance curve, and surface break-down point based upon strokesto temperature variation relationship, whereby there is obtained apermanent record of the scuif resistance and also surface break-down ofthe particular surface treated material tested. Such permanent recordsare kept and are thereafter used for comparative purposes with othercurves subsequently obtained in the testing of other surface treatedmaterials, and also serve to indicate the scuff-resistance andbreak-down point of the material tested.

The foregoing as well as other objects and advantages of this presentinvention will become apparent from the following description taken inconjunction with the drawings, wherein:

FIG. 1 is a view in side elevation of apparatus embodying the presentinvention.

FIG. 2 is an enlarged fragmentary view of a portion of the view taken online IIII of FIG. 1.

FIG. 3 is an enlarged fragmentary view taken on line IlI-III of FIG. 2.

FIG. 4 is a view in perspective illustrating an embodiment of a supportand carrier together with a thermocouple and leads.

As shown in FIG. 1, the novel apparatus includes tester sold on themarket as a CSI-Stoll Flex Tester Model 05494126 of Custom ScientificInstrument Company of Kearny, NJ. Said Flex-Tester 10 includes a housing11 having a switch and control panel 12 in its front face and ahorizontal top plate 14 on which is a fixed guide (not shown) supportinga platen or base 15 which is reciprocable or slidable back and forth onsaid fixed guide. Said platen or base 15 having a flat working face 16,is connected to a constant speed motor through mechanism not shownwhereby upon making of an electric circuit with an A.C. source of supplyby moving the actuator 17 of a switch, the motor is energized to drivethe platen 15 at constant speed back and forth approximately one inch ineach direction on its supporting guide whereby face 16 thereof is soreciprocated in a fixed predetermined path in a single horizontal plane.The reciprocations of the base are counted by a suitable counter 19carried on the panel 12 and may be set at zero at the start of each testin the use of this tester 10. Rigidly secured to and extending upwardlyfrom top plate =14 is a vertical support 21. A pair of parallel links 26are pivotally connected at their rear ends to the support 21 and thefront ends thereof are pivotally connected to a vertical supporting link27 having an upper platen 30 with a flat working face 31, securedthereto at the lower end thereof. The front ends of a pair of parallellinks 32 are pivotally connected to supporting link 27. Said links 32are also pivotally connected to the support 21, and extend rearwardlytherebeyond. A counter Weight 34 of suitable weight is secured to saidlinks 32. The links 26 and C92 in cooperation with link 27 serve as ameans whereby the platen 341 may be moved up or down as required in avertical path at right angles to the face of the lower platen 15 and tomaintain the face 31 of platen 3% parallel to the face 16 of platen 15.The upper end of the link 27 carries a plurality of weights 35. Thenumber and Weight of the Weights 35 is variable depending upon the forceto be exerted by the platen 30. Each of said platens 15 and 30 carriesat the ends thereof rollclamps 37 for securing thereto the ends of thesheet to be tested.

According to this invention a mount 40 of material, having a low heatconductivity characteristic and preferably being in the form of a bandwhich is preferably a cushion of resilient and of a rubbery nature, isadhesively secured to the face 16 of the reciprocable plate 15 at thecenter thereof. The band 41) may be one of a number of differentcompositions, eg. natural or synthetic rubber or of the variousplasticized plastic materials known to the ant. The band 40 which is acushion, is centrally located on the face 16, with its centrallongitudinal axis substantially coincident with the center line of saidplaten along the path of reciprocation thereof. The band 40 may be ofvarious dimensions, but for the purposes of this invention, it isrelatively thin and narrow, and in the embodiment shown is approximatelythree thirty seconds of an inch in thickness and approximately one halfinch in width. The length of the band 40 is preferably considerably lessthan the length of the face 16, but is at least as long as, andpreferably considerably longer than the length of the stroke of theplaten 15. In the embodiment shown, the band ii) is approximately twoinches in length.

A heat sensing means, such as a thermocouple 45, is carried by a mountSt) of material also of low heat conductivity characteristic and beingresilient and of a rubbery nature. The band or mount 5t may be a singlecushion element, but for the sake of ease of production, I employ twoseparate elements 51 and 52 of substantially the same composition,characteristics and dimensions as being parallel.

the band 40. The thermocouple 45 consists of a pair of conductors 47 ofdissimilar metals, and in the present instance are respectively iron andconstantan. Said conductors are respectively covered with insulation,except for the outermost part of the forward ends thereof which arewelded or in any other manner secured together at 46 and the other endsthereof are connected to a graph strip chart recorder 70. Thethermocouple leads or wires 47 are further covered by a flat rubberinsulator 48 which is located between the elements 51 and 52 and theforward ends thereof are bent and extend through an opening in thecentral part of element 51 and the insulated ends 49 are bent over onthe outer face of element 51, with the tip 46 and ends 49 beingpartially embedded in the exposed face of element 51 so that the tip 46and ends 49 are substantially flush with the outer face of element 51.The elements 51 and 52 are secured together with an adhesive to providea unitary two ply structure carrying the thermocouple and leads. Saidtwo ply structure is mounted as shown in FIG. 3, by means of a suitableadhesive to the face 31 of the stationary plate 30. As shown, theelements 51 and 52 as well as the band 40 may be composed of resilientrubber. The width of element 52 may be somewhat greater than that ofelement 51 and the width of element 51 is approximately one half inch inwidth and the length and thickness of each of the elements 51 and 52 maybe the same as the corresponding dimensions of band 40.

As shown in FIG. 3, the two ply band 51) carrying the thermocouple orheat sensor 45 is mounted centrally on face 31, with its longitudinalcenter line being at approximately right angles to the longitudinalcenter line of band 40, and with the working faces of elements 51 and411 Said thermocouple 45 may be Thermocouple B-60912 of Thermo ElectricCompany, Inc. of Saddle River Township, New Jersey.

The thermocouple leads 47 are electrically connected to a graph stripchart recorder 70 connected through as switch (not shown) to an AC.source of supply for recording on a movable graph strip changes intemperature of the thermocouple 45 versus the number of strokes. A typeof such recorder found suitable, and given merely by way of example isModel #153X17 of Brown Instrument Division of Minneapolis-HoneywellRegulator Company. The recorder 70 is well known to those skilled in theart and includes a graph strip 71 which is fed at a constant rate andmeans for recording thereon temperature variations due to the variationsin the thermocouple due to such temperature variations.

In operation, when it is desired to measure the scuffresistance and/orsurface break-downs of a coated-finished, sized or otherwise treatedsurface of one of said materials, and for the purposes of illustration,say of a roll of coated paper, a sample of said coated paper is cut intotwo twin strips 60 and 61 of a width corresponding to that of the band40 and element 51. With the load 35 removed, the plate 30 is raised aconsiderable distance above plate 15 so that samples to be tested may becoupled therewith. Then the strip 60 is laid lengthwise along the lengthof and positioned fiat-wise over the band 41 but with its coated faceexposed and extends beyond either end thereof and is latched to theplate 15 by cam rolls 37 carried thereby. The strip 61 is laidlengthwise along the length of face 31, but transversely of and over andpositioned flat-wise on the bottom face of band 50 and extends beyondthe ends of plate 30 and latched thereto by camrolls 37 carried thereby.Thus the strips 61) and 61 are maintained in taut condition, with thecoated faces thereof being exposed and in parallel planes and with thesensor 45 being in contact with the inner face of the strip '61. Thenthe weight 35 is placed on the spindle of the link 27 whereby the link27 is lowered and that portion of strip 61 over element 51 exerts aforce of desired magnitude and for example about 12 pounds per squareinch on that portion of strip 61 therebelow and in contact therewith.The counter is set at Zero and the switch 17 is actuated to make themotor circuit whereupon the plate 15 reciprocates back and forth atconstant speed with a stroke of about one inch for example in eachdirection and about 112 strokes per minute thereby to so reciprocatestrip 64 with respect ot strip 61 and to subject the coated face of thestrip 61 immediately below element 51 and that portion of the coatedface of strip 61) contacted thereby to a rubbing action therebetweenduring said reciprocation while maintaining them under the constantload.

After said reciprocation is initiated and continues, heat is generatedbetween the contacting surfaces of the strips 611 and 61 whereupon thetemperature of that portion of the strip 61 continuously in contact withstrip 60 increases and then decreases sharply thereby to producecorresponding temperature variations in the sensor 45 in contacttherewith. Simultaneously, with said actuation of switch 17, a switch(not shown) of the recorder 70 is actuated whereupon a graph strip 71 isfed at a constant rate and a recording pen not shown is actuated inresponse to temperature variations in said sensor 45 thereby to recordpermanently on the strip 71 a curve showing temperature variations ofthe thermocouple versus time or number of strokes of the platen 15. Thespeed of travel of the strip 71 is such that in each one-half minute thestrip 71 travels a distance equal to that between a pair of adjacenthori zontal lines shown thereon, and thus of course it travels suchdistance for each 56 strokes of the platen 15. The curve shown on thegraph strip 71 shown in FIG. 1 shows a curve which was produced as aresult of the aforesaid operation. The curve. as shown provides usefulpermanent information of scuff-resistance as shown by the portions 80,81 and 82 thereof and shows the point of surface break-down. As shown inthe particular curve, there is a very high positive temperature gradientat over the first 15 seconds (28 strokes) and a low temperature positivegradient at 8-1 over the next seconds (308 strokes) then a high positivetemperature gradient at 82 over the next 20 seconds (37 strokes) andthen a high negative temperature gradient at 83 which indicates thesurface break-down point which in the present instance occurs at the endof 200 seconds (373 strokes). The curve is a permanent record which maybe interpreted by those skilled in the art to ascertain variouscharacteristics of the surface of materials tested and also may beemployed for comparative purposes.

When the surface break-down point is ascertained by observation in theproduction of the curve, switch 17 is actuated to stop reciprocation andthe recorder is also stopped and that portion of the graph strip havingthe curve thereon is removed therefrom for study and filing.

The stroke counter 19 which reads 373 is re-set at Zero, the load 35 isremoved, the platen 311 is moved upwardly away lfI'OITl platen 15 andthe cam rollers 37 are actuated to release strips 60 and '61 which arenow removed. The apparatus is now ready to receive other strips ofmaterial for testing in the same manner as that heretofore described.

While the present invention has been described in detail it is not to belimited to the exact construction disclosed which is given merely by wayof illustration, for the reason that various changes and modificationsmay be made Without departing from the spirit of this invention.

I claim:

1. Apparatus of the class described comprising a reciprocable firstsupport, a second support movable towards and away from said firstsupport, a face of said first support being opposite a face of saidsecond support whereby said last mentioned face is moved towards andaway from said first mentioned face upon movement of said second supporttowards and away from said first support, a mount for material to betested, said mount being on said face of said first support, a secondmount for material to be tested, said second mount being on said face ofsecond support, with the working faces thereof being in approximatelyparallel planes, each of said mounts being a band of cushion material oflow heat conductivity characteristics, the longitudinal center line ofone of said bands being substantially parallel to the line of the strokeof said reciprocable first support and at approximately right angles tothe longitudinal center line of said other band, means for securing tosaid first support a strip of material to be tested in a positionflat-wise on and extending lengthwise along the length of said mountcarried thereby, means for securing to second support a second strip ofmaterial to be tested in position flat-wise on and extending lengthwiseat approximately right angles to the length of said mount carried bysecond support, with at least a portion of the exposed surface of one ofsaid strips always being in contact with at least a portion of theexposed surface of the other of said strips when said second support isin operative position and said first mentioned support is reciprocating,one of said mounts having an opening therein, temperature variationsensing means, said sensing means extending through said opening andincluding a tip end disposed on the exposed face of said mount havingsaid opening whereby said tip end is disposed adjacent the unexposedsurface of that portion of the strip whose exposed surface is in contactwith the exposed surface of the other strip when said second support isin operative position and said first support is reciprocating, and meansresponsive to temperature variations sensed by said sensing means forrecording said variations.

2. Apparatus of the class described comprising a reciprocable firstsupport, a second support movable towards and away from said firstsupport, a face of said first support being opposite a face of saidsecond support whereby said last menitoned face is moved towards andaway from said first mentioned face upon movement of said second supporttowards and away from said first support, a cushion band on said face ofsaid first support, the longitudinal center line of said band beingsubstantially parallel to the line of stroke of said first support, acushion band on said face of second support, the longitudinal centerline of said band on said face of said second support being atsubstantially right angles to the longitudinal center line of said firstmentioned band, with the working faces thereof being in approximatelyparallel planes, means for securing to said first support a strip ofmaterial to be tested in a position lengthwise along the length of andflat-wise on said cushion carried thereby, means for securing to secondsupport a second strip of material to be tested in position atsubstantially right angles to the longitudinal center line of andflat-wise on said cushion carried by said second support, whereby atleast a portion of the exposed surface of one of said strips will be incontact with at least a portion of the exposed surface of the other ofsaid strips when said second support is in operative position and saidfirst mentioned support is reciprocating, temperature variation sensingmeans carried by said first mentioned cushion b and and including a tipend on the exposed face of said first mentioned cushion band anddisposed adjacent the unexposed surface of that portion of a strip whoseexposed surface is in contact with the exposed surface of the otherstrip when said second support is in operative position and said firstsupport is reciprocating, and means responsive to temperature variationssensed by said sensing means for recording said variations.

3. Apparatus of the class described comprising a reciprocable firstsupport, a second support movable towards and away from said firstsupport, a face of said first support being opposite a face of saidsecond support whereby said last mentioned face is moved towards andaway from said first mentioned face upon movement of said second supporttowards and away from said first support, a mount on said face of saidfirst support, a mount on said face of second support and beingtransverse to said first mentioned mount, means for securing to saidfirst support a 6 strip of material to be tested lengthwise along thelength of said mount and in a position flat-wise on said mount carriedthereby, each of said mounts being a cushion band of low heatconductivity material, one of said bands being multilayer, means forsecuring to said second support a second strip of material to be testedin position transversely of and flat-wise on said mount carried by saidsecond support, whereby at least a portion of the exposed surface ofsaid second mentioned strip will be in contact with at least a portionof the exposed surface of the said first mentioned strip when saidsecond support is in operative position and said first mentioned supportis reciprocating, temperature variation sensing means carried by saidsecondmentioned mount, with the leads thereof located between .a pair ofsaid layers thereof and the tip end thereof located on the exposed faceof said mount and disposed adjacent the unexposed surface of thatportion of a strip whose exposed surface is in contact with the exposedsurface of the other strip when said second support is in operativeposition and said first support is reciprocating, and means responsiveto temperature variations sensed by said sensing means for recordingsaid variations.

4. Apparatus of the class described comprising a reciprocable firstsupport, a sec-ond support movable towards and away from said firstsupport, a face of said first support being opposite a face of saidsecond support whereby said last mentioned face is moved towards andaway from said first mentioned face upon movement of said second supporttowards and away from said first support, a cushion band of low heatconductivity characteristic carried by said first support and disposedcentrally on said face of said first support, the longitudinal centerline of said band being parallel to the line of stroke of said firstsupport, a cushion band of low heat conductivity characteristic carriedby said second support and disposed centrally on said face thereof, withsaid second mentioned cushion being disposed transversely of said firstmentioned cushion, means for securing to said first support a strip ofmaterial to be tested in a position along the length of and flat-wise onsaid cushion carried thereby, means for securing to said second supporta second strip of material to be tested in position transversely of andflatwi-se on said second support, whereby at least a portion of theexposed surface of one of said strips will be in contact with at least aportion of the exposed surface of the other of said strips when saidsecond support is in operative position and said first mentioned supportis reciprocating, temperature variation sen-sing means disposed adjacentthe unexposed surface of that portion of a strip whose exposed sunfaceis in contact with the exposed surface of the other strip when saidsecond support is in operative position and said first support isreciprocating, and means responsive to temperature variations sensed bysaid sensing means for recording said variations.

5 Apparatus of the class described comprising a recipnocable firs-tsupport, a second support movable towards and away from said firstsupport, a face of said first support being opposite a face of saidsecond support whereby said last mentioned face is moved towards andaway from said first face upon movement of said second support towardsand away from said first support, a mount carried by one of saidsupports and disposed centrally on said face thereof, a mount carried bythe other of said supports and disposed centrally on said face thereof,with second mentioned mount being disposed transversely of said firstmentioned mount, each of said mounts being a band of low heatconductivity characteristic, means for securing to one of said supportsa strip of material to be tested in a position along the length of andflatwis'e on said mount carried thereby, means for securing to saidother support a strip of material to be tested in a positiontransversely of and fiatwise on said mount carried thereby, whereby .atleast a portion of the exposed surface of one of said strips will be incontact with at least a portion of the exposed surface of the other ofsaid strips when References Cited in the file of this patent UNITEDSTATES PATENTS Jury June 22, Dennis Feb. 25, Benjamin Apr. 5, Perry Apr.12, Asimow Mar. 23, Frevik July 1, Amen Feb. 5,

1. APPARATUS OF THE CLASS DESCRIBED COMPRISING A RECIPROCABLE FIRST SUPPORT, A SECOND SUPPORT MOVABLE TOWARDS AND AWAY FROM SAID FIRST SUPPORT, A FACE OF SAID FIRST SUPPORT BEING OPPOSITE A FACE OF SAID SECOND SUPPORT WHEREBY SAID LAST MENTIONED FACE IS MOVED TOWARDS AND AWAY FROM SAID FIRST MENTIONED FACE UPON MOVEMENT OF SAID SECOND SUPPORT TOWARDS AND AWAY FROM SAID FIRST SUPPORT, A MOUNT FOR MATERIAL TO BE TESTED, SAID MOUNT BEING ON SAID FACE OF SAID FIRST SUPPORT, A SECOND MOUNT FOR MATERIAL TO BE TESTED, SAID SECOND MOUNT BEING ON SAID FACE OF SECOND SUPPORT, WITH THE WORKING FACES THEREOF BEING IN APPROXIMATELY PARALLEL PLANES, EACH OF SAID MOUNTS BEING A BAND OF CUSHION MATERIAL OF LOW HEAT CONDUCTIVITY CHARACTERISTICS, THE LONGITUDINAL CENTER LINE OF ONE OF SAID BANDS BEING SUBSTANTIALLY PARALLEL TO THB LINE OF THE STROKE OF SAID RECIPROCABLE FIRST SUPPORT AND AT APPROXIMATELY RIGHT ANGLES TO THE LONGITUDINAL CENTER LINE OF SAID OTHER BAND, MEANS FOR SECURING TO SAID FIRST SUPPORT A STRIP OF MATERIAL TO BE TESTED IN A POSITION FLAT-WISE ON AND EXTENDING LENGTHWISE ALONG THE LENGTH OF SAID MOUNT CARRIED THEREBY, 